Security of Supply
Small scale inflows over the weekend have helped to maintain storage across the country. National hydro storage is at 79 % of average for the time of year and continues to hover around the 90th percentile of its historical range.
Storage in Southland continues to recover, and remains comfortably above the Low operating range.
The Maui full production shut down started today and is expected to end in the first half of June.
Demand (733 MW) is similar to last week (731 MW), despite it being the first 5 day working week since 4 April, and getting closer to winter.
Hydro remains the largest part of the generation mix, at 414 GWh while thermal generation continues to make up a large part of the remaining generation mix, at 137 GWh. This reflects low wind generation.
Prices continue to hover around the $200 mark, reflecting the below average hydrology, and upward pressure on thermal fuels including carbon.
The average price at Haywards was $209/MWh, a 1 % increase from $207 MWh last week. Prices peaked on Tuesday 3 May at 11:00 pm during a period of price separation. This was the second period of price separation during the week after the first on 2 May.
HVDC was again more northward this week, with only a few periods of southward flow, North flow was higher on days with low North Island wind generation.
Under Frequency Event
An under frequency event occurred on May 5. See CAN for more information.